Design standards for icons: The independent role of aesthetics, visual complexity and concreteness in icon design and icon understanding

Icons play an important role in modern interfaces and therefore recent empirical research has focused on enhancing icon processing — that is, icon perception and icon function understanding. However, in existing sets, icons vary simultaneously across different icon characteristics, confusing the contribution of each to icon processing. We developed icon design principles for aesthetics, complexity, and concreteness, and used them to create 64 icons that varied independently along each characteristic. Participants reported the icon function and rated each icon in terms of aesthetics, complexity and concreteness. The manipulated characteristics had independent effects on icon processing, with two exceptions, for which we propose evidence-based solutions. Based on these findings we propose guidelines for designing icons for research purposes.

Designable Visual Markers for Mobile Human-Computer Interaction

Enrico Costanza

Visual markers are graphic symbols designed to be easily recognised by machines. They are traditionally used to track goods, but there is increasing interest in their application to mobile human-computer interaction (HCI). By scanning a visual marker through a camera phone, users can retrieve localised information and access mobile services. In particular the dissertation examines the application of visual markers to physical tagging: practices of association of digital information with physical items. One missed opportunity in current visual marker systems is that the markers themselves cannot be visually designed; they are not expressive to humans, and thus fail to convey information before being scanned. To address this limitation, this dissertation introduces the idea of designable markers, visual markers that are both machine-readable and visually communicative to humans, and presents an investigation of the ways in which they can support mobile human-computer interaction. The application of designable visual markers to the creation of mobile interfaces is explored through a variety of methods: through formal usability experiments, through the creation and analysis of example designs, as well as through the qualitative analysis of two field trials. All three approaches were enabled by the engineering and development of d-touch, an actual recognition system that supports designable visual markers and by its integration in a variety of applications and experimental probes. D-touch is based on image topology, and its markers are defined in terms of constraints on the nesting of dark and light regions. The constraints imposed by d-touch are flexible enough to allow novice users to create markers which are visually expressive and at the same time machine readable. A user study demonstrates how such system enables people to design their own functional visual markers, determining their aesthetic qualities and what they visually communicate to others. A desktop application to support users in the creation of valid markers, the d-touch analyser, is presented and its usefulness is demonstrated through the same study. A formal usability experiment comparing five variations of marker-based interfaces on keypad and touch-screen phones shows that all of them allow users to reliably select targets within, on average, less than 4 seconds. Participants of the experiment reported a strong preference for interfaces that involve only marker scanning, compared to those that require a combination of marker scanning and key-presses or touch selections. Example designs of mobile interface generated by the author as well as others are presented to expose how the d-touch recognition system can be integrated in mobile applications. The examples illustrate a variety of ways in which markers can be used to augment printed materials such as cards, books and product packages, adding to them interactive capabilities. The examples show also different approaches to marker design, ranging from simple and recognisable iconic design, to symbols that integrate cues about the interactive functionality, to making them invisible by hiding them in existing graphics. Finally, the dissertation reports and analyses two field trials conducted to study what practices of physical tagging can emerge from, and be supported by, the use of markers. The trials were centred around the use of uWiki, a functional prototype based on d-touch, that allows users to associate digital content to markers printed on physical tags that can be affixed to objects or buildings. Observations show that a variety of practices emerge around the use of this technology, indicating that they provide a rich medium that has potential to attract the interest of real users. Though the results of this work are preliminary, they serve to demonstrate the range of potential for the future of such systems.

EPFL2010

User Interface Design in a Just-in-time Retrieval System for Meetings

Andrei Popescu-Belis, Majid Yazdani

The Automatic Content Linking Device (ACLD) is a just-in-time multimedia retrieval system that monitors and supports the conversation among a small group of people within a meeting. The ACLD retrieves from a repository, at regular intervals, information that might be relevant to the group's activity, and presents it through a graphical user interface (GUI). The repository contains documents from past meetings such as slides or reports along with processed meeting recordings; in parallel, Web searches are run as well. The acceptance by users of such a system depends considerably on the GUI, along with the performance of retrieval. The trade-off between informativeness and unobtrusiveness is studied here through the design of a series of GUIs. The requirements and feedback collected while demonstrating the successive versions show that users vary considerably in their preferences for a given style of interface. After studying two extreme options, a widget vs. a wide-screen UI, we conclude that a modular UI, which can be flexibly structured and resized by users, is the most sensible design for a just-in-time multimedia retrieval system.

Idiap2009

The Complementarity of Tangible and Paper Interfaces in Tabletop Environments for Collaborative Learning

Guillaume Zufferey

The current trend in Human-Computer Interaction aims at bridging the gap between the digital and the real world, exploring novel ways to engage users with computational devices. Computers take new forms that are better integrated into our environment and can be embedded in buildings, furniture or clothes. Novel forms of interfaces take advantage of people's intuitive knowledge of everyday objects to offer more direct and natural interactions. Tangible User Interfaces (TUIs) allow users to interact with digital objects through tangible artifacts, building on their rich physical affordances. Paper User Interfaces (PUIs) add digital capabilities to paper documents, synchronizing for instance their content with their digital counterpart. Unique properties of paper are also used to create engaging and intuitive interfaces to computer applications. This dissertation is interested in the complementarity of tangible and paper interfaces in tabletop environments. We introduce the concept of Tangible and Paper Environments (TaPEs) where Interactive Paper Forms (IPFs), a particular type of PUIs based on the paper form metaphor, are used as a complementary interface to a TUI. We evaluate the potential of IPFs to overcome two main shortcomings of TUIs, in terms of scalability and pedagogy. The scalability issue comes from the limited expressiveness of task-specific physical artifacts, which offer rich physical affordances but limit the complexity of applications that can be controlled by a TUI. The pedagogy issue is raised by the lack of consistent evidence regarding the use of physical manipulatives in educational settings, which is one of the main application domain of TUIs. IPFs overcome the scalability issue by offering a set of generic interaction elements that allow TaPEs to cope with applications of any complexity. In a pedagogical setting, IPFs present learners with abstract representation which facilitate understanding by the embodied and concrete representations offered by tangible artifacts. A TaPE, the Tinker Environment, has been developed with two logistics teachers in the context of the Swiss vocational training system. It consists of a warehouse physical small-scale model (TUI) and TinkerSheets, our implementation of IPFs. It aims at helping apprentices understand theoretical concepts presented at schools. We followed a Design-based Research (DBR) approach: ten studies were conducted during the development of the Tinker Environment in authentic classroom settings. Controlled experiments were conducted to address specific questions. v The general research questions concern the respective affordances of paper and tangible components of TaPEs. The analysis is not limited to usability aspects but also considers their impact on group problem-solving activities and their potential in terms of integration of the system in its context of use. A descriptive model is proposed, built around three interaction circles: individual (usability), group (collaboration) and context (integration). Results identify design guidelines that limit the impact of the less direct interaction modality offered by IPFs, allowing TaPEs to overcome the scalability issue while supporting rich interactions. At the group level, observations of groups of apprentices solving problems around the Tinker Environment show that the consistent physical interaction modality offered by TaPEs naturally supports collaborative interactions. Apprentices tend to take implicit roles based on their location around the system. Regarding the context circle, we observed that carefully designed IPFs play the role of bridges between offline and online activities and contribute to a tight integration of the system in a its context (i.e. a classroom). The specific research questions address the potential of the Tinker Environment in this pedagogical context and its appropriation by teachers. The observations conducted with the Tinker Environment show that the warehouse small-scale model reduces the complexity of problems and allows apprentices to engage in meaningful problem-solving activities. Controlled experiments comparing a TUI to a mulitouch interface demonstrate that tangible artifacts lead to a higher learning gain and an increased performance in a problem-solving activity. Collaboration quality and perceived playfulness are also improved. The teacher plays a central role in the use of the environment, guiding apprentices through activities and encouraging reflections during debriefing sessions. The design of IPFs, emphasizing either their interface or document nature, has a strong influence on their ability to support teachers. We finally discuss the two-way adaptation process that took place between teachers and the system during the development of the Tinker Environment.

EPFL2010

The Complementarity of Tangible and Paper Interfaces in Tabletop Environments for Collaborative Learning

Guillaume Zufferey

EPFL2010

Designable Visual Markers for Mobile Human-Computer Interaction

Enrico Costanza

EPFL2010